The present invention relates to a mobile cleaner for swimming pools or the like, with a suction mechanism for the liquid to be cleaned which has a suction connection, a wet filter arranged in the liquid flow path and a recycling mechanism for the cleaned liquid having a pressure connection and, for example, a pump.
Usually, two different types of devices are used for cleaning swimming pools, particularly the bottom of swimming pools. The aforementioned type of device generally is self-propelled by means of a roller driven by an electric motor and moves over the bottom of the swimming pool and by means of a pump sucks up water with dissolved dirt, forces it through a wet filter on the high pressure or outlet side, usually in the form of a filter bag, and then returns the filtered water to the swimming pool again. In such devices, the pump is part both of the suction mechanism and the recycling mechanism for the cleaned liquid. Such devices are relatively difficult to use and in particular are difficult to remove from the swimming pool again, while having the further disadvantage that they take a relatively long time to clean a swimming pool. On raising the device out of the swimming pool, frequently unfiltered, very dirty water often flows back out of the device into the swimming pool.
The other type of device generally has a suction nozzle guided by a rod or tube and which is connected by a hose to the swimming pool surface suction means, namely the so-called skimmer. The sucked up dirt is held back in the swimming pool filter which is associated in stationary manner with the swimming pool, so that the filter is very rapidly contaminated, e.g. with leaves. There are also very high back flushing losses of the swimming pool water, because such filters must be cleaned by back flushing and removing the back-flushed water. The coarse dirt obtained during the cleaning of the pool also leads to unhygienic contamination of the swimming pool filter, which is constantly in contact with the pool water.
Finally, industrial dirt suction means are known, which can be used for liquids as well as dry dirt. However, such means suck the liquid into a tank which has to be emptied and whose capacity is naturally very limited, even if an additional preliminary water filter is interposed.